get current timestamp in microseconds or milliseconds
in [Shell]
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From: laredotornado on 20 Oct 2009 17:23 Hi, In a shell script (sh), how do I store the time in milliseconds (or microseconds, don't care) to a variable? Thanks, - Dave
From: Janis Papanagnou on 20 Oct 2009 17:48 laredotornado wrote: > Hi, > > In a shell script (sh), how do I store the time in milliseconds (or > microseconds, don't care) to a variable? Where shall the milli-(micro-)seconds come from? (Actual time?) Depending on what shell the 'sh' actually is, in a modern ksh93 you can do ms=${SECONDS#*.} (For plain sh Bourne shells you'd have to rely on external programs.) Janis > > Thanks, - Dave
From: laredotornado on 20 Oct 2009 17:58 On Oct 20, 3:48 pm, Janis Papanagnou <janis_papanag...(a)hotmail.com> wrote: > laredotornado wrote: > > Hi, > > > In a shell script (sh), how do I store the time in milliseconds (or > > microseconds, don't care) to a variable? > > Where shall the milli-(micro-)seconds come from? (Actual time?) > > Depending on what shell the 'sh' actually is, in a modern ksh93 you can do > > ms=${SECONDS#*.} > > (For plain sh Bourne shells you'd have to rely on external programs.) > > Janis > > > > > Thanks, - Dave I meant milliseconds/microseconds from the actual time, yes. I wrote this, but sadly it always produces zero: #!/bin/sh ms=${SECONDS#*.} echo $ms I'm on a Mac OS 10.5.6. Here is what I see in response to uname -a: Darwin ocho.local 9.6.0 Darwin Kernel Version 9.6.0: Mon Nov 24 17:37:00 PST 2008; root:xnu-1228.9.59~1/RELEASE_I386 i38
From: Keith Keller on 20 Oct 2009 18:14 On 2009-10-20, laredotornado <laredotornado(a)zipmail.com> wrote: > On Oct 20, 3:48�pm, Janis Papanagnou <janis_papanag...(a)hotmail.com> > wrote: >> >> Depending on what shell the 'sh' actually is, in a modern ksh93 you can do >> >> � �ms=${SECONDS#*.} >> >> (For plain sh Bourne shells you'd have to rely on external programs.) > > I meant milliseconds/microseconds from the actual time, yes. I wrote > this, but sadly it always produces zero: > > #!/bin/sh > ms=${SECONDS#*.} > echo $ms Well, as Janis wrote, for plain Bourne shells this won't work. It's likely that /bin/sh is a Bourne shell (or a link to bash). > I'm on a Mac OS 10.5.6. Here is what I see in response to uname -a: uname won't really help. You need to know what shell /bin/sh is. But on OS X it's likely bash. I don't think that ksh code will give you what you want anyway; if my reading of the man page is right, it gives you the number of seconds since shell invocation, not absolute milliseconds. (You may need to install a newer version of ksh on your OS X box.) bash has a similar variable (though AFAICT it doesn't do any unit smaller than seconds). What exactly are you trying to accomplish? What is it you're measuring that you think you need milliseconds? --keith -- kkeller-usenet(a)wombat.san-francisco.ca.us (try just my userid to email me) AOLSFAQ=http://www.therockgarden.ca/aolsfaq.txt see X- headers for PGP signature information
From: Glenn Jackman on 20 Oct 2009 18:54
At 2009-10-20 05:23PM, "laredotornado" wrote: > Hi, > > In a shell script (sh), how do I store the time in milliseconds (or > microseconds, don't care) to a variable? Not in the shell, but with per: perl -MTime::HiRes -e 'print int(1000 * Time::HiRes::gettimeofday),"\n"' The overhead of invoking perl will certainly add a few milleseconds... -- Glenn Jackman Write a wise saying and your name will live forever. -- Anonymous |